摘要

The existing physical-layer network coding (PNC) can be grouped into three generic schemes, which are XOR-based PNC, superposition-based PNC, and denoising-and-forward (DNF-based) PNC. Generally speaking, DNF-based PNC has better performance of rate pair region compared with the other two schemes when the transmission is symmetric. When the transmission is asymmetric, its performance is degraded severely. However, superposition-based PNC does not have that limitation even if its rate pair region performance is inferior to that of DNF-based PNC and XOR-based PNC. In this paper, we focus on the combined use of the two PNC schemes, superposition-based PNC and DNF-based PNC, and present a novel PNC scheme called joint superposition and DNF physical-layer network coding (JSDNF-based PNC) as well as the information theory analysis of the achievable rate pair region. At the same time, in the proposed scheme, an adaptive power allocation factor is introduced. By changing the power factor, the system can adapt its rate pair region flexibly. The numerical results show that the proposed scheme achieves the largest rate pair region when the rate difference of two source signals is very large. At the same time, the support on asymmetric transmission is also an important profit of the scheme.